Binary Tree Preorder Traversal

Given the root of a binary tree, return the values in pre-order traversal: visit the current node, then the left subtree, then the right subtree. Implement the traversal and handle an empty tree correctly.

Your question is Binary Tree Preorder Traversal. Start with the requirements in the Question tab.

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Your question is Binary Tree Preorder Traversal. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

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Binary Tree Preorder Traversal

Problem

Constraints